1 Princess Maxima Center for Pediatric Oncology, Utrecht, the Netherlands; Department of Pathology, 12 de Octubre University Hospital, Complutense University of Madrid, Investigation institute I+12, CIBERONC, Madrid, Spain.
2 Department of Medical Oncology, Radboud University Medical Center, Nijmegen, the Netherlands.
3 Department of Pathology, Radboud University Medical Center, Nijmegen, the Netherlands.
4 Department of Surgery, Radboud University Medical Center, Nijmegen, the Netherlands.
5 Princess Maxima Center for Pediatric Oncology, Utrecht, the Netherlands; Department of Pathology, Radboud University Medical Center, Nijmegen, the Netherlands.
6 Department of Medical Oncology, Radboud University Medical Center, Nijmegen, the Netherlands. Electronic address: Yvonne.Versleijen-Jonkers@radboudumc.nl.